JOURNAL OF NEMATOLOGY

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1 JOURNAL OF NEMATOLOGY VOLUME 8 APRIL 1976 NUMBER 2 Revision of the Genus Paratylenchus Micoletzky, 1922 and Descriptions of New Species. Part III of Three parts--gracilacus; D. J. RASKI ~ Abstract: Part 1II covers species with female stylet length ~41 #m which are cottsidered by this author to coutprise the genus C;racilacus Raski, Seven new species of (;racilacus are descrihed and further observations given on 14 other species. ParatyleTwhtts slrenzkei (Volz, 1951) Oostenbrink, 19f~} is transferred to species i~qttirendae. A key to the species of Gracilacus is included. Key Word: taxonomy. This report completes the present revision of the genus Paratylenchus and the related genus Gracilacus. It includes those species in which the females bear a stylet Longer than 41 ttm. The genus Gracilacus Raski, 1962 (10) was proposed for those species of Paratylenchus previously described as ltaving a female stylet greater than 48 t~m and for five new species. Other characters used to distinguish Gracilacus from Paratylenchus were: (i) swollen females found in some species, (ii) most juveniles with elongate stylet, and (iii) excretory pore mostly in region of metacorpus (opposite isthmus in some species). Gracilacus was distinguished from the genus Cacopaurus Thorne, 1943 by the elongation of its body posterior to vulva (tail very short and blunt in Cacopaurus) and a finely annulated cuticle without ornamentation. This concept was not accepted by Siddiqi and Goodey (l l) who synonymized Gracilacus with Paratylenchus. That action of synonymy has been variously received; Received for publication 1 July 'The kind cooperation of many hematologists, including I. Andr~.ssy, M. W. Brzeski, R. C. Colbran, A. l)e(;risse, J. C. Edward, R. P. Esser, E. Geraert, A. M. Golden, D. J. Hooper, W. R. Jenkins, P. A. A. Loof, W. F. Mai, G. Merny, R. H. Mnlvey, B. W. Ngtmdo, J. W. Seinhorst. A. R. Seshadri, S. A. Sher, (;. Swarnp, A. C. Tarjan, G. Thorne and W. M. Wouts, who sent type specimens. identified material, and new collections, is gratefully acknowledged. The technical assistance of N. Jones, U. K. Mehta, H. Chang, and J. Pinochet, especially in mounting and measuring specimens, was most valuable in this study. Professor of Nematology, Department of Nemalolog2/', University of California, Davis it was accepted by Allen and Sher (1) and by Geraert (6), and rejected by Thorne and Malek (12) and by Golden (7). The six new species with long stylets (described since 1962) and tlle seven species (described in this paper) contribnte some new information which supports the concept of this group of nematodes as representing a separate and distinct taxon. The species described by Colbran (3) as Paratylenchus mutabilis indicates a closer relationship between these long-stylet species and Cacopaurus pestis Thorne, 1943 because of the cuticular ornamentation on swollen females of P. mutabilis. On the other hand, some species judged to belong to Gracilacus are found to have what appears to be fourth-stage juveniles with very reduced stylets, a characteristic most frequently found in species of Paratylenchus with female stylets 38/zm or less. This characteristic indicates relationship with Paratylenchus. It is my opinion that these long stylet species are more closely related to Cacopaurus than to Paratylenchus. Gracilacus differs in tail shape from the short, bhmt tail of C. pestis. In addition, senile, swollen females of C. pestis change to brownish, empty cuticular remnants which persist for long periods in the soil. Such forms have not yet been reported for any species of Gracilacus. So far, none of the species of Paratylenchus with stylet 38 /~m or less are known to form swollen females as found in Gracilacus and Cacopaurus. The JOURNAL OF NEMATOI.OGY for January (8: 1-96) was issued 15 January

2 98 Journal of Nematology, Volume 8, No. 2, April 1976 Therefore, it is concluded that Gracilacus should be recognized as a separate genus. MATERIALS AND METHODS The study was based on more than 550 slides holding approximately 2,100 specimens. Most o1: the specimens examined were mounted in glycerin, but the precise methods of killing, fixing, and processing to dehydrated glycerin are not known. After specimens were collected, they were separated from soil by a combined gravityscreening and mist-extraction technique, killed by gentle heat, and fixed in 5% formaldehyde. The specimens then were passed through F.A.A., 2.5% glycerin in 30% alcohol, and 5% glycerin in g0% alcohol. They were allowed to dehydrate from the last solution to glycerin and then were mounted in dehydrated glycerin. Gracilacus Raski, 1962 Diagnosis (emended): Paratylenchidae. Individuals small, less than 0.50 mm. Most juveniles with elongate stylet but some species with reduced stylet in fourth-stage juvenile. Female slender to swollen, with a stylet ~m in length. Body elongate posterior to vulva. Cuticle finely annulated, without ornamentation (except G. mutabilis). Excretory pore generally in region of metacorpus near valve or further anterior, but may be near nerve ring. Male slender, active; styler absent. Caudal alae lacking or at most represented by slight, thickened, cuticular evaginations. Ovary single. Testis one. Type species: Gracitacus epacris (Allen and Jensen, 1950) Raski, 1962 syn. Cacopaurus epacris Allen and Jensen, 1950 Paratylenchus epacris (Allen and Jensen, 1950) Siddiqi and Goodey, 1963 Olher changes: Gracilacus crenata (Corbett, 1966) n. comb. syn. Paratylenchus crenatus Corbett, 1966 Gracilacus micoletzkyi (Edward, Misra and Singh, 1967) n. comb. syn. Paratylenchus micoletzkyi Edward, Misra and Singh, 1967 Gracilacus robusta (Wu, 1974) n. comb. syn. Paratylenchus robustus Wu, 1974 Endings of specific names are changed throughout to conform with feminine gender of Gracilaeus. Gracilacus aonli (Misra and Edward, 1971) n. comb. syn. Paratylenctms aonli Misra and Edward, 1971 Type specimens have not been accessible and judgment of G. aonli is based on the pnblished description. The authors (8) consider G. aonli to be most closely related to G. goodeyi and G. straeleni. The head of G. aonli is described as "truncate conoid," hut in the illustrations it appears to be more rounded in outline. G. aonli also is descrihed as having oval spermatheca, but there are no detailed drawings indicating its precise structure. In some species, the spermatheca is oval and is about the same in length as in width, whereas the elongate, ovoid spermatheca of G. goodeyi and of G. pandata is very long, 2 to 3 times as long as the corresponding body diam. The shorter stylet (44-56 /~m) and conical head of G. goodeyi appear to be distinctive from G. aonli (stylet= ~m). The distinction of G. aonli from G. stroeleni seems to be based on the spherical spermatheca of G. slraeieni as contrasted with the oval spermatheca of G. aonli. Also the esophagous is shorter in G. straeleni (b = vs in G. aonli) and the tail more rounded in G. aonli (finely rounded to acute in G. straeleni). Gracilacus abietis (Eroshenko, 1974) n. comb. syn. Paratylenchus abietis Eroshenko, 1974 Type specimens have not been accessible so judgment is based on the published description. The evidence indicates the author's diagnosis of relationship with G. straeleni is correct (5). The characteristics used to distinguish G. abietis from G. straeleni are not entirely convincing. The

3 Revision of Paratylenchus Part III--Gracilacus: Raski 99 smooth head of G. abietis may be a dependable character (as it is in Paratylenchus profectus) although it is not common in these genera. Other species have been considered to have the head smooth or without amndation, but occasionally fine head annulation is apparent. Tile corpus, described and illustrated as being narrow in the anterior half and then swelling to nearly twice that diameter in posterior half, also seems distinctive but has not been noted or used heretofore. The position of hemizonid relative to the excretory pore is not dependable as a specific character in other species. It has been found to vary from anterior to posterior in various specimens of the same population. The range of 'V' values in the paratypes (76-82) is more anterior than the composite for all the populations of G. straeieni reported in this paper. Until more collections of this nominal species are made, and more specimens are available for examination, the diagnosis is acknowledged as given and G. abietis is considered a distinct species. Gracilacus acicula (Brown, 1959) Raski, 1962 Two slides identified by G. L. Brown as G. acicula were loaned by the Canadian National Collection of Nematodes for this study. One slide had I3 females, I male and 1 juvenile (labelled paratypes) from pasture sod at Met Bleu, Ontario. The second slide contained 5 females from meadow sod near Nesbitt, Manitoba, which was reported in the original description as a record of its distribution. This species also has been found in soil with mixed roots from several plant species in a nursery near Winter Park, Florida. There are 32 females and 9 males in that collection. Two of the females retained the fourth-stage cuticle with very short prorhabdions attached. No juveniles were found. The juvenile described by Brown (2) as having a stylet 34 ttm long probably is the third stage. One other collection, identified tentatively as G. acicula, has three females from soil in a greenhouse at Michigan State University, Ingham County, Michigan. Unfortunately these are considerably flattened and some characters are difficult to discern. The tails are more slender-conoid and finely rounded than those of most females seen in other collections. In all other respects, these specimens fit G. acicula. Gracilacus acuienta (Brown, 1959) Raski, 1962 Two slides with 35 female and 4 male paratypes were loaned by the Canadian National Collection of Nematodes for this study. These are not from the type locality but from grass sod in Gatineau Park, Quebec, which was reported by Brown (2) as one of the distribution records of G. aculenta. These specimens conform closely with the original description. Five new collections, identified as G. aculenta, are reported here. One is from soil about the roots of a mixture of plants (including cactus) near tile tide line at Bayside, Texas. Dimensions are as follows: 7 females: L =.28 ( ) mm; a = 23 (19-26); b = 2.7 ( ); V = 74 (73-76); stylet = 51 (48-53) t~m. 3 males: L ( ) mm; a = 28 (27-30); c = 12 (10-14). Another collection is from a tea plantation, Balanoor Estate, Balehonnur District, Karnataka State, India. The dimensions are: 5 females: L =.25 ( ) ram; a = 21 (17-25);b = 2.4 ( );c = 15;V = 75 (74-76); stylet = 54 (53-56) /~m; prorhabdion = 48 (47-50) ~m; excretory pore = 76 (69-89)/~m. 3 males: L =.27 ( ) mm; a = 26 (23-30); c = 12 (11-13); spicules = 16 (15-18) ~m; gubernaculum = 4 (3-4) /~m; T = 32 (26-44); excretory pore = 59 (54-64) ~m. The Texas sample also held specimens of P. minutus and the Balanoor Estate sample held specimens of P. neoamblycepkalus. The other three collections, identified as G. aculenta, inclnded 12 females, 1 male and 1 juvenile from soil about the roots of sagebrush at German Flats, Salina, Utah; 9 females from grassy soil at Gobbler Spring, Williams, Arizona; and 2 females, 3 males in natural grassland at Matador, Saskatchewan, Canada; 5 females, 1 male from strawberry at Strzeloe, Poland. Some of these specimens, including some labelled paratypes, have an inconspicuous lateral vulvar membrane which is

4 100 Journal of Nematology, Volume/, No. 2, April 1976 not clearly present in most of the specimens. In all other respects, they resemble G. aculenta and are so considered in this paper. A small lateral vulvar membrane indicates close relationship of G. idalima with G. aculenta, which differs in stylet length [58 (54-62) t~m for G. aculenta vs. 83 (75-88) t~m for G. idalima]. A composite of the dimensions of all five collections is: Female: L =.29 ( ) mm; a = 23 (17-28); b = 2.7 ( ); c = 12 (10-15); V = 72 (69-76); stylet = 57 (,t8-68) ~m; excretory pore = 73 (59-89) t~m. Male: L =.31 ( ) ram; a = 27 (23-30); c = 13 (10-15); spicules = 18 (15-21) t~m; gubernaculum = 4 (3-5) /zm; T = 33 (26-44); excretory pore = 66 (54-77) tlm. Gracilacus epacris (Allen and Jensen, 1950) Raski, 1962 G. epacris from three new locations in California has been added to the UCNS Collection, Davis. Two females and 1 juvenile were found in soil about the roots of California laurel, UmbeIlularia californica Nutt., near Fairfield, Solano County. A single female was found in soil about the roots of U. californica near Shell Beach, Marin County. Three females and I juvenile were found in soil about the roots of Quercus sp. near Livermore, Alameda County. This is the same locality in which 17 females, 8 males and 4 juveniles were found in soil about the roots of Platanus racemosa Nutt. The measurements and descriptions of juveniles reported by Raski (10) were based on these specimens from P. racemosa but a reference to the host source was not inclnded in that report. Gracilacus goodeyi (Oostenbrink, 1953)Raski, 1962 Two slides with 10 females labelled as paratypes of P. goodeyi are on deposit in the U(]NS Collection, Davis. Three other slides with six females labelled as /'. goodeyi from Arnheim, The Netherlands (and apparently from the type collection also) are in the UCNS Collection. Unfortunately, all the specimens on the five slides are flattened beyond recognition. Nine other collections from six different countries have been identified as G. goodeyi. According to Geraert (6), the elongate spermatheca of G. goodeyi is an important character differentiating it from closely related species. It may be 3 times as long at the corresponding body diameter. The identification of G. goodeyi as having an elongate spermatheca is at variance with the published description by Oostenbrink (9). He described the spermatheca as round. This character must be confirmed in other type specimens since the paratypes at University of California, Davis, are useless. Another character which distinguishes G. goodeyi is the conoid head which presents a narrow tapering outline with fine but definite annules and is rounded at the apex. This appearance may be more pronounced in mature, swollen females. The tail of G. goodeyi also is more often subacute to finely rounded as contrasted with that of the related species, G. straeleni, which has an acute or pointed tail outline. It is doubtful that the male described by Oostenbrink is indeed G. goodeyi. Two other species of Paratylenchus were reported in that type collection of soil about a pear tree near Arnheim. One of those could be P. hamatus, males of which bear a stylet. A similar situation was found in a collection from Austria in which one male of Paratylenchus was found with 9 females of G. goodeyi, 1 female of P. microdorus, and 1 female which appears to be P. neoamblycephalus. The male has no stylet but does have fairly well-defined caudal alae, a characteristic which is unique for a male of Paratylenchus. Geraert (6) reports a male of G. goodeyi without stylet. So many collections are mixtures of species that it is very difficult to associate specimens of one sex with the appropriate opposite sex. Mono-specific collections are invaluable for resolving such problems. The nine collections mentioned previously include 8 females from strawberry soil near Gliwice-Labedy, Poland; 6 females from grass and weed soil, Laffrey, France; 5 females from grass and weed soil, Digne, France; 6 females, Jembloux, Belgium; 9 females from grass soil, Innsbruck, Austria; 14 females in soil at roots of Lolium, Agrostis and Festuca, at Kirton, Lincolnshire, England; 2 females from old meadow soil, Limburg (Gronsveld), The Netherlands; 1 female from arable soil, Ruurlo,

5 Revision of Paratylenchus Part III--Gracilacus: Raski 101 The Netherlands; 9 females from soil in garden at queen's palace, Soestdijk, The Netherlands. Except for stylet length, all these specimens fit the description of G.. oodeyi. Several females have stylets which are shorter (the shortest being 44 /tin) than the minimum reported in the type collection. Thus the range of stylet length is 44-56/tm. Gracilacus intermedia Raski, 1962 A collection of 6 females identified as G. intermedia was made from soil about roots of Pinus ponderosa Dougl. and Chamaebatia [oliolosa Benth. near Volcano, Anlador County. Also present were specimens of G. straeleni. Other collections include a single female of G. intermedia from California laurel, Umbellularia californica Nutt., near Fairfield, Solano County, together with G. epacris and G. straeleni; 2 females from grapevine near Napa, Napa County; 2 females, 2 juveniles from prunes in Sonoma County; and 1 female from cypress, Cupressus sp., on the University of California Berkeley campus together with Para tylench us neoa rn blycephalus. Gracilacus ivorensis (Luc and de Guiran, 1962) n. comb. syn. Paratylenchus ivorensis Luc and de Guiran, 1962 Paratypes, 7 females and 1 male, of this species were available for study. The specimens conform closely with the description, but I noted a greater range of variability in female tail shape than was illustrated. The tails of some females end in an extremely fine, acute terminus and one female has a rather bluntly rotmded tail terminus. Gracilacus macrodora (Brzeski, 1963) n. comb. syn. Paratylenchus macrodorus Brzeski, 1963 Paratylenchus Iongistylosa Dement'eva, 1972 n. syn. Eight females and 3 juvenile paratypes of G. macrodora were available for study. The female paratypes fit the description precisely. The juveniles were measured as follows: (3 second stage?): L =.25 ( ) ram; a = 20 (18-21); b = ; stylet = 45 (43-49) /tin; prorhabdion = 38 (37-39) ~Lm. Head similar to that of female. Tail conoid; tip subacute to rounded. Developing gonad 9-11 tlm long (about 5/zm wide), ttm tyom terminus. Another collection of 4 females and 21 juveniles from a peach nursery at Chateauneuf du Luc, near Valence, France was also identified as G. macrodora with dimensions as follows: 4 females: L =.32 ( ) mm; a = 24 (21-27); b = 2.6 ( ); V = ~-' (10-2~ 77 (74-78); stylet = 81 (75-86); prorhabdion = 74 (68-80) ~tm; excretory pore = 82 (79-86) ttm. 3 juveniles (fourth stage?): L =.31 ( ) ram; a = 23 (22-24); b = 4.2 ( ); stylet = lacking; excretory pore = 70 ~tm. Head as in female of G. macrodora. Excretory pore opposite posterior bull). Gonad /tin long, ~m from terminus. Tail slender conoid; tip rounded. No specimens of P. longistylosa were available for study and the conclusion that it is synonymous with G. macrodora is based on the published description. The diagnosis of P. longistylosa (4) indicates that it is most closely related to P. macrophallus, a conclusion which is doubtful. In appearance and most measurements, it is more closely related to G. macrodora. Range of total length (given as mm for P. longistylosa) is the only major difference noted [for G. macrodora L =.34 ( ) ram], and this is not sufficient for specific differentiation. Gracilacus mira Raski, 1962 Specimens identified as G. mira have been collected from five new localities in California. One female was collected fronl soil about roots of Arctostaphylos sp. in Mix Canyon near Vacaville, Solano County. The collection also held specimens of Paratylenchus neoamblycephalus and G. straeleni. Fifteen females and 7 juveniles were collected from soil about roots of California juniper,.luniperus cali[ornica Cart., and 3 females from soil about roots of Rhus trilobata Nutt. in Joshua Tree National Monument, San Bernardino County. Eight females of Paratylenchus variabilis Raski, 1975 also were found in the Rhus trilobata sample. Three females and 1 juvenile were collected about roots of Tartarian cherry on Mahaleb rootstock near

6 102 Journal of Nematology, Volume 8, No. 2, April 1976 Linden, San Joaquin County. Four females were collected about prunes in Tehama County and 1 female from peach near Modesto, Stanislaus County. GraciIacus mutabilis (Colbran, 1969) n. comb. syn. Paratylenchus mutabilis Colbran, 1969 Four slides with 10 females, 3 males, and 4 juveniles from the type locality (two of the slides labelled paratypes), were available for this study. The adults are precisely as described by Colbran. The juveniles, two of which were in the process of molting, appear to be third stage. Dimensions of the juveniles are as follows: L = toni; a = 17-18; b = ; stylet = /,m; prorhabdion = 26-29/~m; excretory pore = 69 /,m. Head similar to that of adult females with distinctly rounded submedian lobes not set off by constriction. Excretory pore opposite isthmus. Tail conoid, subacute to bluntly rounded. One specimen showed a conspicuous parasite similar to the one illustrated in G. pandata n. sp. Gracilacus oostenbrinki (Misra and Edward, 1971) n. comb. syn. Paratylenchus oostenbrinki Misra and Edward, 1971 G. oostenbrinki is diagnosed by the authors (8) as being related to G. peratica, G. intermedia and G. mira. Its description, however, indicates it is more closely related to G. macrodora. The greater size of G. macrodora ( mm vs mm for G. oostenbrinhi) and position of excretory pore (near stylet knobs in G. mira vs. opposite nerve ring in G. oostenbrinhi) is evidence these are two separate and distinct species. Gracilacus peratica Raski, 1962 Four new records of this species were from samples taken in Italy. Five females, 2 males, and 9 juveniles were identified from soil collected near Pescara. Thirteen females, 2 males, and 5 juveniles were found in soil about roots of olive near Molise, Campobasso. Three females were found in soil about roots of Paulsen grape hybrid 1103 in the government nursery near Palermo, Sicily. Also present in that sample were specimens of Paratylenchus baldacci Raski, 1975 and Paratylenchus nainianus Edward and Misra, Six swollen females were recovered directly from roots of Laurus nobilis L. near Bari together with 5 swollen females of Rotylenchulus macrodoratus Dasgupta, Raski and Sher, Gracilacus robusta (Wu, 1974) n. comb. syn. Paratylenchus robustus Wu, 1974 Specimens of G. rob usta were not available for this study. According to tile description and illustration (14), G. robusta has a number of characters to support a relationship with G. straeleni. The range of total length, 'V' value, position of excretory pore opposite isthmus, and rounded head with fine annules are all similar to G. straeleni. However, the presence of a spermagonium is unique for this genus and also for Paratylenchus. Because ot ~ the spermagonium and the greater stylet length [55 (44-66) /,m for G. straeleni vs /,m for G. robusta], this species is accepted as distinct and separate. Gracilacus steineri (Golden, 1961) Raski, 1962 syn. Paratylenchus steineri Golden, 1961 Three slides with single female paratypes were available for this study. In addition, a single slide with 4 females and 1 male, identified as G. steineri, was sent by R. C. Colbran from soil around a native legume at Western Ridge, corner of west Road, Mt. Tamborine, Australia. These have the following dimensions: 4 females: L =.29 ( ) mm; a = 26 (24-29); b = 2.4 ( ); V = 76 (76-77); styler = 73 (68-75) /,m; excretory pore = 86 (75-96)/~m. 1 male: L =.35 ram; a = 33; c = 15; spicules = 17 /,na; gubernaculum = 4 tim; T = 32; excretory pore /,m. The stylet of these specimens is longer but overlaps the range described for G. steineri. In other respects these specimens and G. steineri are considered conspecific. Gracilacus straeleni (de Coninck, 1931) n. comb. syn. Procriconema straeleni

7 Revision of Paratylenchus Part IlI--Gracilacus: Raski 103 de Coninck, 1931 Paratylenchus audriellus Brown, 1959, n. syn. ParatyIenchus straeleni (tle Coninck, 1931) Oostenbrink, 1960 Paratylenehus sarissus Tarjan, 1960 There are no original type specimens of G. straeleni extant. Geraert (6) reported a collection from moss anti soil from the type locality, Baraque Michel, Liege, Belgium, in which he found one female. He briefly described that specimen and designated it as neotype. Eight collections, identified as G. straeleni, from Europe were studied in this review. One collection from sphagnum moss at Gribsee-Moor, Denmark held 11 females and 1 male. No other species of Paratylenchus or Gracilacus were present. This is the first record of a male of G. straeleni from Europe. The dimensions for that population are as follows: 5 females: L =.39 ( ) mm; a = 24 (22-25); b = 3.6 ( ); c = 13 (12-13); V = :,2 1~,-4~) 81 (80-82); stylet = 60 (57-63) /~m; prorhabdion = 47 (45-49) ttm; excretory pore = 93 (88-98) /~m. 1 male: L =.36 ram; a = 30; c = 10; spicules = 21 t~m; gubernaculum = 5 /~m; T = 28; excretory pore = 82 #m. Two female and 2 male paratypes of G. sarissa were studied. Also 14 female and 5 male paratypes of G. audriella were loaned from the Canadian National Collection of Nematodes for this review. On the basis of the synonymy of these two species with G. straeleni, 31 collections from the U. S. A. and Canada, 11 of which have 1 or more males, have been identified as G. straeleni. Females and males also were found in 1 collection from New Zealand. The decision of Geraert (6) that G. sarissa is a synonym of G. straeleni is accepted. Geraert further judged that G. straeleni is not so different from G. audriella and noted that G. audriella has a more sharply pointed tail and shorter stylet. Brown (2) stressed the hook-like terminus of the tails in both males and females of G. audriella as a distinguishing character. In fact, the paratypes show conoid, sharply-pointed tails on some females as well as typical hook-like processes on others. In all other respects, these paratypes con- form closely with G. straeleni. Therefore, it is concluded G. audriella is a synonym of G. straeleni. Other collections from the U. S. A. and Europe show similar variations with a longer styler more typical of G. straeleni. The specimens are strong evidence that G. straeleni is widely distributed and has a variable tail shape and a variable stylet length. A composite of all the previous identifications indicates a species with the following ranges of dimensions: Female: L =.37 ( ) ram; a = 23 (16-30); b = 3.5 ( ); c = 12 (10-14); V = 82 (79-85); styler = 55 (44-66) ttm. Male: L =.37 ( ) mm; a = 31 (28-35); c = 12 (10-15); spicules = 22 (21-24) /tin; gubernaculum = 4 (4-5) t~m; T = 27 (24-35); excretory pore = 83 (79-90) /tm. New distribution records in California include: Cypress, Cupressus sp., near Bolinas, Matin County; California laurel, Umbeltularia cali[ornica Nutt., near Fairfield, Solano County, near Willits, Mendocino County, and on the American River near Auburn, Placer County; soil on University of California Berkeley campus; Pinus attenuata Lemmon and Arctostaphylos sp., Moraga Ridge, Contra Costa County; Black sage, Artemesia arbuscula Nutt., Badger Canyon; Quercus sp., Mt. Diablo, Contra Costa County; Quercus sp., near Monticello, Napa County; Quercus sp., and Pinus sp., Hobo Gulch Camp, Trinity County; Quercus sp., near Vacaville, Solano County; Quercus sp., Tecate area, San Diego County; Quercus sp., near San Lucas, Monterey County; Quercus sp., near Millbrae; Camellia japonica L., Huntington Gardens, Los Angeles County; Opuntia sp., locality unknown; grassy soil, Asilomar; Pinus ponderosa Dougl. and Charnaebatia [oliolosa Benth., near Volcano, Amador County; Aesculus californica (Spach) Nutt., in Mix Canyon, near Vacaville, Solano County; and redwoods and U. cali]ornica, on a stream bed in Henry Cowell Redwoods State Park, near Felton, Santa Cruz County. Distribution records in other states include: Grey birch roots and soil, Lafayette Campground, Franconia Notch, New Hampshire; Quercus sp., Great Smoky National Park, Tennessee; pecan grove, Byron, Georgia; Pinus sp., 9.7 km south of

8

9 " Revision ot7 Paratylenchus Part III-Gracilacus: Raski 105,, :),~.C~31(!,, )....- /.~.I ~..:... t " i /! /:. :-~.::.../._ / j i [--r.-:::::: :; ;.s-.(:., '- f ' [// i'? i",, ' ~.)!";i: U I Io,p, ) [, ~W:;? 'I 7 / 1 Y< >li,'-, t i ii~:i <i~i.. <~ '! [ t,, I -:k. li.tl { 11,( :~":>!:~,".~I _"-.... "..: <,,I /s,.",,,?, " t il,i j / '~,,/// / I :':"T7 : "~.~ ~,x'~ Y - ~ /. 3 50y. ' ~,6 ~ 6 -:?is;; I 0/,.,~ W/".-'~/ ~I-4 7,8 FIG Gracilacus latescens n. sp. Body rather broad, narrowing only slightly to rounded head with slightly projecting, rounded submedian lobes as in female. Stylet small; knobs only slight swellings. Body contents coarsely granular throughout; details of internal morphology obscured. Tail bluntly rounded. Developing gonad appears to be 9-10 /~m long, tan from terminus; suggests second stage. No juveniles with elongate stylet present. Two slender females in last molt present inside a swollen female. Each molted cuticle with prorhabdion 9 /zm long. Holotype: Female, collected by C. M. Heald on January 22, 1973, slide number 1446, UCNS Collection, Davis, California.

10 106 journal of Nematology, Volume 8, No. 2, April 1976 A llotype: Male, same data as holotype, slide number 1447, UCNS Collection, Davis, California. Paraiypes: 40 females, 104 swollen females, 8 males, 87 juveniles, same data as holotype, deposited as follows: I1 females, 43 swollen females, 1 male, 45 juveniles in UCNS Collection, Davis, California; 22 females, 53 swollen females, 3 males, 37 juveniles in USDA Nematode Collection, Beltsville, Maryland; 4 females, 2 swollen females, 1 male, 5 juveniles in National Nemotode Collection, IARI, New Delhi, India; 1 female, 2 swollen females, 1 male each at Nematology Department, Rothamsted Experimental Station; Plantenziektenkundige Dienst, Wageningen, The Netherlands; UCNS Collection, Riverside, California. Type host: Mesquite, Prosopis sp. Type locality: Weslaco, Texas. Diagnosis: This species is most closely related to G. aculenta from which it differs in longer stylet [58 (51-66) /zm for G. aculenta] and length of esophagus (b = in G. aculenta). Distribution: 9 females, 3 males and 2 juveniles found in soil about roots of Mesembryanthernum sp. at Dillon Beach, Matin County, California; 7 females, 2 males and 3 juveniles from soil about strawberry, Noyo, Mendocino County, California. Gracilacus costata n. sp. (Fig. 9-15) Paratypes (13 females): L =.31 ( ) mm; a = 25 (22-29); b = 2.4 ( ); c (11-12); V = ~'~ (12-ls~ 70 (67-72); stylet (70-87) /~m; prorhabdion = 69 (63-78) #m; excretory pore = 69 (56-79) /zm. Paratypes (4 males): L =.34 ( ) ram; a = 28 (26-31); c = 11 (11-12); spicules = 20 (18-22) ~m; gubernaculum = 5 (4-6) /~m; T = 37 (33-41); excretory pore = 66 (62-72) t~m. Holotype (female): L mm; a = 26; b = 2.3; c ~- 11; V = 17 71; stylet = 79 ~tm; prorhabdion ~- 70 ~m; excretory pore = 64 t~m. Body strongly curved almost a closed 'C' shape after fixation. Body narrows gradually anteriorly to a rounded head. Submedian lobes or lips not set off; rounded anteriorly to same level as lateral lobes; produce a somewhat flat or truncate anterior surface. Sclerotization light; stylet guiding apparatus appears as two dark lines slightly curved at level of retracted stylet tip. Stylet slender; knobs rounded; apparently slightly anteriorly directed. Length of stylet shaft plus knobs 9 /~m (7-9 ~m in paratypes). Excretory pore anterior to base of stylet (Fig. 9). Hemizonid inconspicuous, immediately posterior to excretory pore. Esophago-intestinal valve small, rounded. Ovary outstretched (Fig. 13); spermatheca inconspicuous (Fig. 10), without sperm. Vulva lips slightly rounded and protruding; lateral vulvar membranes lacking. Tail long, slender-conoid; annules very fine but visible; subacute, to finely rounded terminus. Body annules average about 1.0 ~m in width; lateral field with 3 incisures equally spaced; center line less distinct than outer 2 (Fig ). Allotype (male): L mm; a = 28; c = 12; spicules = 18 /~m; gubernaculum = 5/ml; T -- 37; excretory pore = 63 #m. Body an open 'C' shape after fixation. Body narrows gradually anteriorly to rounded head. Submedian lobes slightly rounded, not set off; lateral area slightly depressed; give concave anterior outline. Sclerotization light. Stylet lacking, esophagus degenerate; only remnants identifiable (Fig. 14). Excretory pore immediately anterior to hemizonid which extends about 3 body annules in length. Testis outstretched; anterior third with large developing cells; posterior portion filled with small sperm. Spicules slightly curved; cloacal sheath short without projecting posterior margin. Tail slender conoid; annules visible almost to acute terminus (Fig. 15). Body annules average about 1.0 /~m in width; lateral field with 3 incisures equally spaced; center line less distinct than outer 2. Juveniles (3 fourth stage?): L =.28 ( ) ram; a = 18 (15-22); b = 3.6 ( ); stylet = 11 (10-13)/~m; prorhabdion = 7 (6-7) /~m; excretory pore (64-73) /~m. Head rounded with submedian lobes or lips as in female; rounded but not set off. Stylet very weakly developed; knobs small swellings. Excretory pore at level of isthmus. Developing gonad not distinct. Tail subacute to rounded. Holotype: Female, collected by L. H.

11 " :"\ Revision of Paratylenchus Part IiI--Gracilacus: Raski 107 ~,,~: Y\\\ \ I~' HI I /.... ~ \~x~'f ~ "./. ;>:? ~:.. t i y F:!II \... i.,. ~)y:: ~, \, "" -9 : : "" >: " '" r,, \. \\",,,..' 'I I,-I,.,i : '1 \ iii:::::,!."?" " t }i j : : / L ~' GI'. I,I /:?-/,~ > 7TG\ : ~:~:... I: A" 9?- l b, /. I '~ d I,) h) L/X I.~.,,b',:/ IZlG ) Oracilacus costata n. sp ) Gracilacus solivaga n. sp. Wang on May 21, 1967, slide number 1442, holotype except these were collected on UCNS Collection, Davis, California. May 15, 1967, deposited as follows: 8 females, 13 males and 10 juveniles in UCNS AlIotype: Male, same data as holotype, Collection, Davis, California; 1 female, 1.slide number 1443, UCNS Collection, Davis, male each at USDA Nematode Collection, C.alifornia. Beltsville, Maryland; National Nematode Paratypes: 11 females, 8 males, 9 ju- Collection, IARI, New Delhi, India; Nemaveniles, same data as holotype plus 2 re- tology Department, Rothamsted Experimales, 10 males, 1 juvenile, same data as mental Station, Harpenden, England;

12 108 Journal o/nematology, Volume 8, No. 2, April 1976 Plantenziektenkundige Dienst, Wageningen, The Netherlands; UCNS Collection, Riverside, California. Type habitat: Noncultivated loam soil. Type locality: Mt. Yangmin, Taipei, Taiwan. Diagnosis: This species is most closely related to G. solivaga n. sp. from which it differs in its greater length [L =.24 ( ) mm for G. solivaga] and slender-conoid subacute tail (tail mostly deformed in G. solivaga). G. costata is also related to G. latescens from which it differs also in larger size [L =.27 ( ) mm for G. latescens] and subacute tail (tail is bluntly rounded in G. latescens). Distribution: 11 females, 2 males and 20 juveniles from soil about Manihot utilissima Pohl., at the property of Rafael Navarro A. in Colombia, South America. Gracilacus soiivaga n. sp. (Fig ) Paratypes (5 females): L =.24 ( ) ram; a = 24 (22-25); b = 2.1 ( ); c =?; V = 14 (13-,4~ 73 (71-75); stylet = 71 (69-75) /zm; prorhabdion = 64 (60-69) tim; excretory pore = 54 (52-56)/tm. Holotype (female): L =.25 ram; a = 25; b = 2.1; c =?; V ~ a4 71; stylet = 74 ttm; prorhabdion = 69 ~m; excretory pore = 52 ttm. Body an open 'C' shape after fixation. Body gradually narrows anteriorly to a rounded head. Sclerotization very light; styler guiding apparatus appears as two slightly arcuate, darker lines at tip of retracted stylet. Styler slender; slightly arcuate ventrad (Fig. 17). Knobs small, rounded; slightly posteriorly directed. Stylet shaft plus knobs 5 /~m (6-7 in paratypes). Excretory pore about 2 body widths anterior to stylet knobs. Hemizonid immediately posterior to excretory pore. Isthmus slender, relatively short. Esophago-intestinal valve small, rounded. Ovary outstretched; spermatheca indefinite; no sperm seen (Fig. 19). Vulva inconspicuous; lateral vulvar membranes lacking. Tail long, slender-conoid; narrows gradually; annules distinct to misshapen; lobed terminus [paratypes variously misshapen, two subacute-conoid (Fig. 18)]. Body annules fine; less than 1 ttm in width. Lateral field with 3 incisures (Fig. 16), center one lighter than outer 2. Male: Unknown. Holotype: Female, collected by M. T. Hutchinson on March 22, 1962, slide number 1448, UCNS Collection, Davis, California. Paratypes: 5 females, same data as halotype, deposited in UCNS Collection, Davis, Cali fornia. Type habitat: Upper jungle soil. Type locality: Mooloya, Hewaheta, Sri Lanka. Diagnosis: This species is most closely related to G. costata from which it differs in its smaller size [.31 ( ) mm for G. costata] and its variously misshapen tail (uniformly subacute in G. costata). Also present in this soil sample were 13 females, 2 males, and 1 juvenile of Paratylenchus minutus. Gracilacus pandata n. sp. (Fig ) Paratypes (10 females): L =.38 ( ) mm; a (23-32); b ( ); c = 11 (9-12); V = 2z (19-31) 74 (70-76); stylet = 66 (63-70) /~m; prorhabdion = 55 (53-59) /~m; excretory pore = 11)3 (94-119) ttm. Paratypes (3 males): L =.39 ( ) mm; a =?; c = 10; spicules (19-22) #m; gubernaculum = 4 (4-5); T = 36 (34-40); excretory pore (83-94)/~nl. Holotype (female): L =.40 mm; a = 28; b = 3.1; c = 11; V = 29 75; stylet = 68 ~m; prorhabdion = 55 ttm; excretory pore = 102 #m. Body only slightly curved ventrad after fixation. Body gradually narrows slightly to rounded head. Submedian lobes small rounded; protrude only very slightly beyond round contour of head. Sclerotization light; styler guiding apparatus appears as two dark, slightly curved lines at tip of retracted stylet. Stylet slender, slightly curved; knobs large, rounded, slightly posteriorly directed. Excretory pore at level of anterior end of isthmus (opposite nerve ring in some paratypes). Hemizonid 2 body annules in length at level of excretory pore. Esophago-intestinal valve small, rounded. Ovary outstretched; sper- matheca narrow, elongate (7 x 25 /tm); filled with large sperm (Fig. 22). Vulva inconspicuous; only a slight notch in ventral outline. Lateral vulvar membrane rounded, prominent. Tail long, slender-conoid ending in narrow, finely rounded, almost acute

13 Revision of Paratylenchus Part III--GraciIacus: Raski 109 :l l ~,~/~.y,,i/t // i t ~! ',. 23 l i /i,! 25 I0 M.~, i l :: ::::.:S: ~":'! I LI i'~l t'(*" * ~"\ ', : ",: I,'}, \'~ ~, 7..!.~ \ ~\ \ / ' "k :. \~. 5..7::-:"" ' i] 1! /ik', I : fly FIG ) Gracilacus pandata n. sp. Fig. 20) Two specimens ot: Bacillus penetrans present on anterior end of female ) Gracilacus parvula n. sp. terminus. Body annules average /~m wide. Lateral field with 4 incisures (Fig. 21); inner 2 lighter than outer 2 [several paratype females had conspicuous, infections of Bacillus penetrans (syn. Dubosqia penetrans) on cuticle, especially on anterior end (Fig. 20)]. Allolype (male): L =.36 mm; a =?; c = 10; spicules /~m; gubernaculum = 4/nn; T = 31; excretory pore = 87 /~m. Body an open 'C' shape after fixation. Body narrows gradually to slender, rounded head. Sclerotization very light; styler lacking (Fig. 23). Testis outstretched. Spicules slightly curved, ventrad. Cloacal sheath short, inconspicuous, without projection of posterior margin. Tail slender, conoid; terminus finely rounded (Fig. 24). Holotype: Female, collected by F. E. Caveness on August 31, 1964, slide number 1399, UCNS Collection, Davis, California. Allotype: Male, collected by F. E. Caveness on July 10, 1964, slide number 1400, UCNS Collection, Davis, California. Paratypes: 26 females, same data as holotype, and 1 female, 3 males, same data as allotype, deposited as follows: 22 females, 3 males in UCNS Collection, Davis, California; 1 female each in National Nematode Collection, IARI, New Delhi, India;

14 110 Journal of Nematology, Volume 8, No. 2, April 1976 USDA Nematode Collection, Beltsville. Maryland; Nematology Department, Rothamsted Experimental Station, Harpenden, England; Plantenziektenkundige Dienst, Wageningen, The Netherlands; UCNS Collection, Riverside, California. Type host: Grapefruit (holotype); water yam, Dioscorea alata L. (allotype). Type locality: 1 mile north of Katsina Twp., Katsina Province, Nigeria (holotype); 8 miles southwest of Jebba, Ilorin Province, Nigeria (allotype). Diagnosis: This species is most closely related to G. goodeyi from which it is distinguished by its longer stylet (63-70 tzm vs tzm for G. goodeyi) and rounded head (conoid in G. goodeyi). Gracilacus parvula n. sp. (Fig ) Paratypes (4 females): L =.35 ( ) mm; a = 28 (27-29); b = 3.3 ( ); c = 16; V = 25 ~,oa-2s) 79 (78-80); stylet = 58 (56-60) /,m; prorhabdion = 46 (45-48) /~m; excretory pore = 91 (86-96) /,m. Holotype (female): L =.35 mm; a = 28; b = 3.3; c -- 17;V = 28 79); stylet ~m; prorhabdion = 47 t,m; excretory pore = 89 /,m. Body an open 'C' shape after fixation. Head narrows with rounded outline, distinct annules, to constriction setting off rounded, protruding submedian lobes or lips, truncate or flattened at anterior surface. Sclerotization light; stylet guiding apparatus appears as two dark lines, slightly arcuate, near tip of retracted styler (Fig. 26). Styler slender; knobs relatively large, directed slightly posteriad. Excretory pore opposite iqhmus. Hemizonid 3 body annules in length immediately anterior to excretory pore. Length of stylet shaft plus knobs 12 t,m (11-12 txm in paratypes). Isthmus slender, relatively short. Esophago-intestinal valve small, lobate. Ovary outstretched; spermatheca small, ovate, without sperm. Vulva inconspicuous; lateral vulvar membranes distinct, rounded (Fig. 27). Tail conoid; narrows gradually to bluntly rounded terminus (Fig. 28). Lateral field with 4 incisures about equally spaced; inner 2 lighter than outer 2 (Fig. 25). Male: Unknown. Juvenile (4 third stage?): L ( ) mm; a = 22 (22-23); b = 2.6 ( ); stylet = 40 (38-42) /,m; prorhabdion ~ (30-34) /~m; excretory pore = 70 (61-80) /,m. Head with distinct set-off lips as in female. Stylet knobs large, backwardly directed. Excretory pore opposite isthmus. Gonad about 21 /,m long, /~m from terminus. Tail bluntly rounded. Holotype: Female, collected May 15, 1967, slide number 1449, UCNS Collection, Davis, California. Paratypes: 4 females, 11 juveniles, same data as holotype, deposited in UCNS Collection, Davis, California. Type habitat: Noncultivated loam soil. Type locality: Mt. Yangmin, Taipei, Taiwan. Diagnosis: This species is most closely related to G. mutabilis but differs in the set-off protruding lips of G. parvula (in G. mutabilis the head outline is continuous, not set off, but with submedian lobes rounded anteriorly). The stylet is longer in G. mutabilis [58 (56-60) /~m vs /,m for G. mutabilis]; stylet knobs of G. parvula larger than in G. mutabilis. Additional collection: After this manuscript was submitted for publication but before it was set for printing, another collection of this species was provided by C. S. Huang. The collection held 10 males, 5 juveniles, and 7 females from soil about roots of Sunki orange rootstock near Chiayi, Taiwan in May Measurements of males and females and a description of the male by C. S. Huang are: 12 females (Chiayi): L =.35 ( ) ram; a = 24 (19-30); b ( ); c = 16 (15-19); v = 82 (81-84). 9 males (Chiayi): L =.31 ( ) ram; a = 29 (27-30); c = 14 (11-16); spicules = 19 (17-20) /,m. Male (Chiayi): Body shape after fixation variable. Some an open 'C' shape; others tightly curved; tail overlapping body. Body gradually narrows anteriorly, then more abruptly at rounded head. Sclerotization delicate. Stylet lacking. Hemizonid anterior to excretory pore; occupies about 3 body annules in length. Testis outstretched. Cloacal opening with prominent sheath and hooked posterior margin. Spicules slender, curved. Caudal alae not observed, Tail narrows gradually with slender

15 Revision of Paratylenchus Part III-Gracilacus: Raski 111 conoid shape; terminus finely rounded, most acute. Gracilacus enata n. sp. (Fig ) Paratypes (16 females): L =.31 ( ); a = 26 (23-28); b = 2.3 ( ); c = 12 (11-13); V =,7 (1~-.~0) 78 (74-80); stylet = 94 (82-104) ffm; prorhabdion = 83 al- (72-92) /~m; excretory pore = 90 (80-110) #m. Paratypes (2 males): L = mm; a ; c = 10; spicules = /zm; gubernaculum = 3 /~m; T = 31-38; excretory pore = ffm. Holotype (female): L =.35 ram; a = 27; b = 2.4; c = 12; V = ~7 77; stylet = 104 ffm; prorhabdion = 92 /zm; excretory ii, i ', 11! / ~; ', r:::: t ' 38 / J (-,':,<., :..:.,,. :7 ~/ io /~',t i//, ', i \,\ ;... )t,;i ',.~_i I,..., FIG ) Gracilacus enata n. sp ) Gracilacus teres n. sp. 35

16 112 Journal of Nematology, Volume 8, No. 2, April 1976 pore = 97 /ma. Body only slightly curved ventrally after fixation. Body gradually narrows anteriorly; ends in a constriction or depression setting off sub-median lobes or lips which are rounded and protrude forward. Sclerotization light; stylet guiding apparatus appears as two dark lines, slightly curved, near tip of retracted stylet (Fig. 29, 30). Stylet slender, with rounded knobs. Length of stylet shaft plus knobs 12 /~m (8-14 tim in paratypes). Excretory pore anterior to styler knobs. Ovary outstretched (Fig. 32); spermatheca spherical (spherical to slightly ovate in paratypes). Rounded vulvar lips protrude slightly. Lateral vulvar membranes absent. Tail slender conoid; annules distinct up to narrow, acute terminus. Body annules average less than 1 t~m in width. Lateral field with 4 incisures equally spaced and distinct (Fig. 31). Allotype (male): L =.34 ram; a = 36; c --- 9; spicules = 17 ~m; gubernaculum = 4 /~m; T = 31; excretory pore = 75 t~m. Body an open 'C' shape; curved dorsally after fixation. Body gradually narrows anteriorly to a slender rounded head. Sclerotization light; stylet lacking (Fig. 33). Hemizonid at level of excretory pore. Testis outstretched; sperm small. Testicular gland prominent. Spicules curved slightly; cloacal sheath short, without protrusion of posterior margin. Caudal alae not observed. Tail slender, conoid; terminus finely rounded, almost acute (Fig. 35). Body annules average less than 1 tim in width. Lateral field with 4 incisures equally spaced and distinct (Fig. 34). Juveniles (4 second stage?): L =.23 ( ) ram; a (18-23); b = 2.6 ( ); styler = 49 (45-51) t~m; prorhabdion = 41 (38-43) tan; excretory pore = 70 (64-77) ~m. Body narrows at head to set-off protruding lips or submedian lobes similar to female. Stylet slender; distinct and welldeveloped knobs directed posteriad. Excretory pore at level of isthmus. Gonad 7 (6-8) t~m long, 59 (55-65) ~m from terminus. Tail slender, conoid; ends in finely rounded terminus. Juveniles (6 fourth stage): L ( ) mm; a = 24 (21-27); b = 3.3 ( ); excretory pore = 81 (66-89) ttm. Body narrows at head to set-off protruding lips or submedian lobes similar to females. Stylet lacking. Procorpus elongate. Excretory pore at level of isthmus. Gonad 39 (29-50) t~m long, 70 (65-77) ~m from terminus. Tails slender, conoid; some narrow abruptly near terminus and give hook-like or digitate appearance. Terminus finely rounded to acute. Holot)~pe: Female, collected by A. Lizana on September 26, 1968, slide number 1444, UCNS Collection, Davis, California. A llotype: Male, same data as holotype, slide number 1445, UCNS Collection, Davis, California. Paratypes: 24 females, 2 males, 18 juveniles, same data as holotype, deposited as follows: 17 females, 2 males, 12 juveniles in UCNS Collection, Davis, California; 3 females, I juvenile in USDA Nematode Collection, Beltsville, Maryland; 1 female, 4 juveniles in National Nematode Collection, IARI, New Delhi, India; I female, 1 juvenile in Nematology Department, Rothamsted Experimental Station, Harpenden, England; 1 female each in Plantenziektenkundige Dienst, Wageningen, The Netherlands, and UCNS Collection, Riverside, California. Type host: Custard apple, or Chirimoya var. Concha Temarana, Annona cherimola Mill, Type locality: Quillota, Chile. Diagnosis: This species is most closely related to G. teres n. sp. from which it differs in the longer stylet [74 (72-75) /~m for G. teres] and acute tail (rounded in G. I eres). Gracilacus teres n. sp. (Fig ) Paratypes (14 females): L =.31 ( ) mm; a = 21 (19-25); b = 2.6 ( ); c = 13 (10-15); V = 18 ~t~-20) 74 (72-75); stylet ~ 74 (69-83) /zm; prorhabdion (64-77) t~m; excretory pore = 77 (70-85) /~m. Paratypes (6 males): L =.35 ( ) mm; a = 30 (29-31); b = 3.9; c = 16 (15-17); spicules (16-19) /~m; gubernaculum = 4 /zm; T = 35 (34-37); excretory pore ~ 71 (55-80)/~m. Holotype (female): L =.30 ram; a = 21; b = 2.4; c = 13; V = 20 74; stylet = 7.'~ tzm; prorhabdion = 67 /~m; excretory pore = 78 ~m. Body after fixation an open 'C' shape; more strongly curved posterior

17 to vulva. Body very gradually narrows anteriorly, with distinct annules up to slight constriction which sets off small, rounded, submedian lobes or lips. Lateral lips rounded, at same level with submedian lobes, give tri-lobed outline which is rounded (almost truncate outline in some paratypes). Sclerotization of head, light; styler guiding apparatus appears as two dark straight lines near tip o[ retracted styler (Fig. 39). Stylet slender; curves dorsad more than curvature of body; knobs small, rounded. Length of styler shaft plus knobs 6 /~m (5-7 t~m in paratypes). Dorsal gland orifice not visible because esophageal hnnen coils. Excretory pore at level between stylet knobs and valve of median bulb. Small hemizonid at level of excretory pore. Isthmus slender, elongate. Esophago-intestinal valve distinct, small, lobate. Ovary outstretched; spermatheca inconspicuous, without sperm (Fig. 40). Vulva inconspicuous without lateral vulvar membranes. Tail conoid; narrows gradually, with distinct annules almost to bluntly rounded terminus. Body annules average btm ira width. Lateral field with 4 incisures, equally spaced about 1 t~m apart, inner 2 lighter than outer 2 (Fig. 38). Allotype (male): L =.38 mm; a = 31; c = 15; spicules = 18 ~tm; gubernaculum = 4 ~tm; T = 36; excretory pore = 80 ~m. After fixation, body coils tightly, especially in posterior portion. Body gradually narrows anteriorly, then narrows more abruptly near lips to set-off small protruding lips or submedian lobes which are somewhat like holotype head but lips do not protrude so distinctly. Sclerotization delicate; stylet lacking (Fig. 37). Hemizonid 2 body annnles posterior to excretory pore. Testis outstretched, surrounded in posterior portion by prominent testicular gland. Spicules curved slightly. Cloacal sheath distinct, without hook-like extension o[ posterior margin. Tail narrows gradually to conoid outline, with bluntly rounded terminus (Fig. 36). Body annules average ~m in width. Lateral field very faint, with 4 incisures equally spaced; inner 2 lighter than outer 2. [uveniles (5 fonrth stage?): L =.34 ( ) ram; a = 21 (17-25); b = 4.1 ( ); stylet = 16 (15-19) t~m; prorhabdion = 13 (11-15)~tm; excretory pore (72- Revision of Paratylenchus Part III--Gracilacus: Raski ) ~m. Head rounded similar to female. Styler much reduced, knobs slight swellings. Excretory pore near posterior end of metacorpus. Developing gonad 16-4l t~m long, /~m from bluntly rounded terminus. Holotype: Female, collected by R. D. Sharma in 1973, slide number 1450, UCNS Collection, Davis, California. Allotype: Male, same data as holotype, slide number 1451, UCNS Collection, Davis, California. Paratypes: 14 females, 6 males, 19 juveniles, same data as holotype, deposited as follows: 6 females, 1 male, 17 juveniles in UCNS Collection, Davis, California; 2 females, 1 male, 1 juvenile in National Nematode Collection, IARI, New Delhi, India; 2 females, 1 male in USDA Nematode Collection, Beltsville, Maryland; 1 female, 1 male, 1 juvenile in Nematology Departlnent, Rothamsted Experimental Station, Harpenden, England; 1 female, 1 male each at Plantenziektenkundige Dienst, ~:ageningen, The Netherlands, and UCNS Collection, Riverside, California. Type host: Theobroma cacao L. Type locality: Linhares, Espirito Santo, Brazil. Diagnosis: This species is most closely related to G. steineri and G. enata n. sp. It differs from G. steineri in its set-off, protruding lips (bead rounded in G. steineri) and longer stylet [67 (65-69) slm for G. steineri]. It differs from G. enata by its rounded tail (acute in G. enata) and shorter stylet [94 (82-104) /~m in G. enata]. Distribution: Four other collections, all from T. cacao, were identified as this species. One is from Linhares, the type locality of G. teres; two others are from the same general area of Espirito Santo; and the fourth is from Mutuipe at Fazenda do Dr. Rni. SPECIES INQUIRENDAE Paratylenchus strenzkei (Volz, 1951) Oostenbrink, 1960 syn. Hemicycliophora ( = Procriconema) strenzkei Volz, 1951 There are no type specimens of P. strenzkei. Volz (13) described his specimens as juveniles, but undoubtedly the vulva was mistaken for the anus, and they were indeed females.